3.8.3 Update the Amazon RDS Security Group

When you configure the new Amazon EC2 instance to access the Amazon RDS database, the final step is to add the instance security group to the Amazon RDS security group. This process is very similar to what you did earlier when you added the Amazon Lightsail IP address range to the Amazon RDS security group.

1. Go to the details page for the Amazon EC2 instance and ensure your new instance is selected.
2. Click the ‘Description’ tab.
3. Next to the ‘Security groups’, click your security group.
4. Copy the ‘Group ID’ to your clipboard.
5. Navigate to the Amazon RDS databases page.
6. From the list of databases, click the name of the Amazon RDS database you created earlier to access the database details screen.
7. Ensure the ‘Connectivity’ tab is selected.
8. In the ‘Connectivity’ section, click the name of the security group for your RDS database.
9. Click the ‘Inbound’ tab to access the rules that define which traffic is allowed to reach the RDS database.
10. Click ‘Edit’
11. Click ‘Add Rule’ then configure:
    • ‘Type:’ MYSQL//Aurora
    • =CIDR, IP or Security Group:/ Paste in the value of the EC2 instance security group you noted previously.
    • Click ‘Save’
12. Navigate to the IP address of your EC2 instance, and you should see the todo application up and running.